Abstract:
:The translocation of molecules across cellular membranes or through synthetic nanopores is strongly affected by thermal fluctuations. In this work we study how the dynamics of a polymer in a noisy environment changes when the translocation process is driven by an oscillating electric field. An improved version of the Rouse model for a flexible polymer has been adopted to mimic the molecular dynamics, by taking into account the harmonic interactions between adjacent monomers and the excluded-volume effect by introducing a Lennard-Jones potential between all beads. A bending recoil torque has also been included in our model. The polymer dynamics is simulated in a two-dimensional domain by numerically solving the Langevin equations of motion. Thermal fluctuations are taken into account by introducing a Gaussian uncorrelated noise. The mean first translocation time of the polymer centre of inertia shows a minimum as a function of the frequency of the oscillating forcing field. This finding represents the first evidence of the resonant activation behaviour in the dynamics of polymer translocation.
journal_name
Phys Bioljournal_title
Physical biologyauthors
Pizzolato N,Fiasconaro A,Adorno DP,Spagnolo Bdoi
10.1088/1478-3975/7/3/034001subject
Has Abstractpub_date
2010-08-04 00:00:00pages
034001issue
3eissn
1478-3967issn
1478-3975pii
S1478-3975(10)46955-1journal_volume
7pub_type
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